Exercise, Nutrition, and Bone Health

Optimal bone metabolism is the result of hormonal, nutritional, and mechanical harmony, and a deficit in one area is usually impossible to overcome by improvements in others. Exercise during growth influences bone modeling locally at the regions being loaded, whereas calcium is thought to act systemically to influence bone remodeling. Despite acting through different mechanisms, a growing body of research suggests that exercise and calcium may not operate independently. Low dietary calcium intake or reduced bioavailability may minimize the adaptive response to exercise-induced bone loading. Conversely, adequate levels of calcium intake can maximize the positive effect of physical activity on bone health during the growth period of children and adolescents. Research also suggests that adequate levels of calcium intake can maximize bone density at the regions being loaded during exercise. Achieving optimal bone health and minimizing one’s risk of osteoporotic fracture later in life depend on a lifelong approach. This approach relies on the establishment of an optimum level of bone during the growth years, with a subsequent goal to maintain and slow the rate of age-related bone loss thereafter. Exercise, adequate nutrition, and optimal hormone levels are the components that influence the bone outcome. Making healthy nutritional choices, engaging in weight-bearing physical activity, and ensuring optimal hormone levels during growth provides a window of opportunity to build optimal bone mass, to reduce the risk of fracture later in life. Concurrent management of fracture risk with a physical activity prescription, adequate nutrition, and pharmacotherapy for osteoporosis when required offers the best approach to optimal bone health throughout adulthood.

The Yonder project: Stories of impact, change, and capacity building through engagement in arts education

This thesis examined the long-term impact of the community arts education project Yonder, a collaboration between Education Queensland and Queensland Performing Arts Centre. The findings from the data reveal that the project was still having impact twelve months after its completion and that in some instances the project served as a 'circuit-breaker', especially for special needs students and struggling students. The intervention of a rich arts project proved to be an opportunity for these students to learn in a different way and to perceive themselves in a new and reinvented light. This confidence was found to transfer into other aspects of their learning.

Medical education and law: Withholding/withdrawing treatment from adults without capacity

BACKGROUND Law is increasingly involved in clinical practice, particularly at the end of life, but undergraduate and postgraduate education in this area remains unsystematic. We hypothesised that attitudes to and knowledge of the law governing withholding/withdrawing treatment from adults without capacity (the WWLST law) would vary and demonstrate deficiencies among medical specialists. AIMS We investigated perspectives, knowledge and training of medical specialists in the three largest (populations and medical workforces) Australian states, concerning the WWLST law. METHODS Following expert legal review, specialist focus groups, pre-testing and piloting in each state, seven specialties involved with end-of-life care were surveyed, with a variety of statistical analyses applied to the responses. RESULTS Respondents supported the need to know and follow the law. There were mixed views about its helpfulness in medical decision-making. Over half the respondents conceded poor knowledge of the law; this was mirrored by critical gaps in knowledge that varied by specialty. There were relatively low but increasing rates of education from the undergraduate to continuing professional development (CPD) stages. Mean knowledge score did not vary significantly according to undergraduate or immediate postgraduate training, but CPD training, particularly if recent, resulted in greater knowledge. Case-based workshops were the preferred CPD instruction method. CONCLUSIONS Teaching of current and evolving law should be strengthened across all stages of medical education. This should improve understanding of the role of law, ameliorate ambivalence towards the law, and contribute to more informed deliberation about end-of-life issues with patients and families.

Biomarkers of exercise-induced myocardial stress in relation to inflammatory and oxidative stress

Increased concentrations of biomarkers reflecting myocardial stress such as cardiac troponin I and T and brain natriuretic peptide (BNP) have been observed following strenuous, long-lasting endurance exercise. The pathophysiological mechanisms are still not fully elucidated and the interpretations of increased post-exercise concentrations range from (i) evidence for exercise-induced myocardial damage to (ii) non-relevant spurious troponin elevations, presumably caused by assay imprecision or heterophilic antibodies. Several lines of evidence suggest that inflammatory processes or oxidative stress could be involved in the rise of NT-proBNP and Troponin observed in critically ill patients with sepsis or burn injury. We tested the hypothesis that inflammatory or oxidative stress is also responsible for exercise-induced cardiomyocyte strain in a large cohort of triathletes following an Ironman triathlon. However, the post-race increase in cardiac troponin T and NT-proBNP was not associated with several markers of exercise-induced inflammation, oxidative stress or antioxidant vitamins. Therefore, we clearly need more studies with other inflammatory markers and different designs to elucidate the scientific background for increases in myocardial stress markers following strenuous endurance events.

No indications of persistent oxidative stress in response to an ironman triathlon

Introduction: Training for and competing in ultraendurance exercise events is associated with an improvement in endogenous antioxidant defenses as well as increased oxidative stress. However, consequences on health are currently unclear. Purpose: We aimed to examine the impact of training- and acute exercise-induced changes in the antioxidant capacity on the oxidant/antioxidant balance after an ironman triathlon and whether there are indications for sustained oxidative damage. Methods: Blood samples were taken from 42 well-trained male triathletes 2 d before an ironman triathlon, then immediately postrace, 1, 5, and 19 d later. Blood was analyzed for conjugated dienes (CD), malondialdehyde (MDA), oxidized low-density lipoprotein (oxLDL), oxLDL:LDL ratio, advanced oxidation protein products (AOPP), AOPP:total protein (TP) ratio, Trolox equivalent antioxidant capacity (TEAC), uric acid (UA) in plasma, and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in erythrocytes. Results: Immediately postrace, there were significant increases in CD, AOPP, TEAC, UA (for all P < 0.001), and AOPP:TP (P < 0.01). MDA rose significantly (P < 0.01) 1 d postrace, whereas CD (P < 0.01), AOPP (P = 0.01), AOPP:TP (P < 0.05), and TEAC (P < 0.001) remained elevated. OxLDL:LDL trended to increase, whereas oxLDL significantly (P < 0.01) decreased 1 d postrace. Except for GSH-Px (P = 0.08), activities of SOD (P < 0.001) and CAT (P < 0.05) significantly decreased postrace. All oxidative stress markers had returned to prerace values 5 d postrace. Furthermore, several relationships between training status and oxidative stress markers, TEAC, and antioxidant enzyme activities were noted. Conclusions: This study indicates that despite a temporary increase in most (but not all) oxidative stress markers, there is no persistent oxidative stress in response to an ironman triathlon, probably due to training- and exercise-induced protective alterations in the antioxidant defense system.

Exercise-induced DNA damage: Is there a relationship with inflammatory responses?

Both a systemic inflammatory response as well as DNA damage has been observed following exhaustive endurance exercise. Hypothetically, exercise-induced DNA damage might either be a consequence of inflammatory processes or causally involved in inflammation and immunological alterations after strenuous prolonged exercise (e.g. by inducing lymphocyte apoptosis and lymphocytopenia). Nevertheless, up to now only few studies have addressed this issue and there is hardly any evidence regarding a direct relationship between DNA or chromosomal damage and inflammatory responses in the context of exercise. The most conclusive picture that emerges from available data is that reactive oxygen and nitrogen species (RONS) appear to be the key effectors which link inflammation with DNA damage. Considering the time-courses of inflammatory and oxidative stress responses on the one hand and DNA effects on the other the lack of correlations between these responses might also be explained by too short observation periods. This review summarizes and discusses the recent findings on this topic. Furthermore, data from our own study are presented that aimed to verify potential associations between several endpoints of genome stability and inflammatory, immune-endocrine and muscle damage parameters in competitors of an Ironman triathlon until 19 days into recovery. The current results indicate that DNA effects in lymphocytes are not responsible for exercise-induced inflammatory responses. Furthermore, this investigation shows that inflammatory processes, vice versa, do not promote DNA damage, neither directly nor via an increased formation of RONS derived from inflammatory cells. Oxidative DNA damage might have been counteracted by training- and exercise-induced antioxidant responses. However, further studies are needed that combine advanced -omics based techniques (transcriptomics, proteomics) with state-of-the-art biochemical biomarkers to gain more insights into the underlying mechanisms.

Endurance exercise and DNA stability: Is there a link to duration and intensity?

It is commonly accepted that regular moderate intensity physical activity reduces the risk of developing many diseases. Counter intuitively, however, evidence also exists for oxidative stress resulting from acute and strenuous exercise. Enhanced formation of reactive oxygen and nitrogen species may lead to oxidatively modified lipids, proteins and nucleic acids and possibly disease. Currently, only a few studies have investigated the influence of exercise on DNA stability and damage with conflicting results, small study groups and the use of different sample matrices or methods and result units. This is the first review to address the effect of exercise of various intensities and durations on DNA stability, focusing on human population studies. Furthermore, this article describes the principles and limitations of commonly used methods for the assessment of oxidatively modified DNA and DNA stability. This review is structured according to the type of exercise conducted (field or laboratory based) and the intensity performed (i.e. competitive ultra/endurance exercise or maximal tests until exhaustion). The findings presented here suggest that competitive ultra-endurance exercise (>4h) does not induce persistent DNA damage. However, when considering the effects of endurance exercise (<4h), no clear conclusions could be drawn. Laboratory studies have shown equivocal results (increased or no oxidative stress) after endurance or exhaustive exercise. To clarify which components of exercise participation (i.e. duration, intensity and training status of subjects) have an impact on DNA stability and damage, additional carefully designed studies combining the measurement of DNA damage, gene expression and DNA repair mechanisms before, during and after exercise of differing intensities and durations are required.

DNA damage in response to an Ironman triathlon

The major aims of this study were to investigate the effect of an Ironman triathlon on DNA migration in the single cell gel electrophoresis assay, apoptosis and necrosis in the cytokinesis-block micronucleus cytome assay with lymphocytes and on changes of total antioxidant capacity in plasma. Blood samples were taken 2 days (d) before, within 20 min, 1 d, 5 d and 19 d post-race. The level of strand breaks decreased (p<0.05) immediately after the race, then increased (p<0.01) 1 d post-race and declined (p<0.01) until 19 d post-race. Apoptotic and necrotic cells decreased (p<0.01) and the total antioxidant status increased (p<0.01) immediately after the race. The results indicate that ultra-endurance exercise does not cause prolonged DNA damage in well-trained male athletes.

Impact of endurance and ultraendurance exercise on DNA damage

Regular moderate physical activity reduces the risk of several noncommunicable diseases. At the same time, evidence exists for oxidative stress resulting from acute and strenuous exercise by enhanced formation of reactive oxygen and nitrogen species, which may lead to oxidatively modified lipids, proteins, and possibly negative effects on DNA stability. The limited data on ultraendurance events such as an Ironman triathlon show no persistent DNA damage after the events. However, when considering the effects of endurance exercise comparable to a (half) marathon or a short triathlon distance, no clear conclusions could be drawn. In order to clarify which components of exercise participation, such as duration, intensity, frequency, or training status of the subjects, have an impact on DNA stability, more information is clearly needed that combines the measurement of DNA damage, gene expression, and DNA repair mechanisms before, during, and after exercise of differing intensities and durations.

Benefits and barriers to exercise in midlife women undertaking a web-based multi-modal lifestyle intervention for the primary prevention of chronic disease

Chronic diseases are a leading cause of death and disability, largely attributable to modifiable lifestyle risk factors. Many midlife Australian are getting insufficient physical activity for health and face a range of barriers to exercise. Results of this study provide evidence that benefits and barriers are an important predictor of exercise behaviour in midlife women and, that a 12 week nurse led health promotion program can effectively promote benefits and increase physical activity. This study provides evidence about benefits and barriers to exercise that will inform health promotion practice for chronic disease risk factor reduction in midlife women.

The peer leader capacity building model: A student learning journey

The benefits of peer leader experiences in building graduate skills and capabilities, is well documented and recognised in the higher education sector (Ender & Kay, 2001; Lindsey, Weiler, Zarich, Haddock, Krafchick, & Zimmerman, 2014; Shook & Keup, J., 2012). While benefits are acknowledged, responsibility for identifying, structuring and recording the learning experiences and learning outcomes is charged to the student. This poster describes a framework ‘The Peer Leader Capacity Building Model’ that purposefully structures the peer-leader’s learning journey providing: timely training, moments of critical reflection and goal setting. The model articulates the fundamental interplay of learning and peer leader service which forms the peer ‘learnership’. The journey begins with the ‘aspiration’ phase where students come to understand their leadership opportunities, progressing through ‘enabling’ and ‘mastering’ phases where students shape their learner-leader experience, and finally, to the ‘contributing graduate’ phase where students emerge as competent graduates able to confidently participate in their communities and workplaces. In shifting from a program centric approach that priorities the needs of the mentees, the Peer Leader Capacity Building Model focuses on the individual as a peer leader encouraging the student to shape their individual ‘learnscape’ through consciously navigating both their curricula and co-curricular learning experiences.

Outdated journal rankings and the ERA exercise

As the results of the latest Excellence in Research Australia (ERA) exercise come closer to being announced, universities around Australia are holding their collective breaths. The ERA claims to be an assessment of research strengths and quality at Australian universities. While it is not supposed to produce a set of league tables, ultimately that is what tends to happen...

Engaging a multiple-track approach to building capacity for 21st Century engineering, opportunities and challenges for rapid curriculum renewal

‘Complexity’ is a term that is increasingly prevalent in conversations about building capacity for 21st Century professional engineers. Society is grappling with the urgent and challenging reality of accommodating seven billion people, meeting needs and innovating lifestyle improvements in ways that do not destroy atmospheric, biological and oceanic systems critical to life. Over the last two decades in particular, engineering educators have been active in attempting to build capacity amongst professionals to deliver ‘sustainable development’ in this rapidly changing global context. However curriculum literature clearly points to a lack of significant progress, with efforts best described as ad hoc and highly varied. Given the limited timeframes for action to curb environmental degradation proposed by scientists and intergovernmental agencies, the authors of this paper propose it is imperative that curriculum renewal towards education for sustainable development proceeds rapidly, systemically, and in a transformational manner. Within this context, the paper discusses the need to consider a multiple track approach to building capacity for 21st Century engineering, including priorities and timeframes for undergraduate and postgraduate curriculum renewal. The paper begins with a contextual discussion of the term complexity and how it relates to life in the 21st Century. The authors then present a whole of system approach for planning and implementing rapid curriculum renewal that addresses the critical roles of several generations of engineering professionals over the next three decades. The paper concludes with observations regarding engaging with this approach in the context of emerging accreditation requirements and existing curriculum renewal frameworks.

Analysis of arm elevation muscle activity through different movement planes and speeds during in-water and dry-land exercise

Objective The objectives of this cross-sectional, analytical inference analysis were to compare shoulder muscle activation at arm elevations of 0° to 90° through different movement planes and speeds during in-water and dry-land exercise and to extrapolate this information to a clinical rehabilitation model. Methods Six muscles of right-handed adult subjects (n = 16; males/females: 50%; age: 26.1 ± 4.5 years) were examined with surface electromyography during arm elevation in water and on dry land. Participants randomly performed 3 elevation movements (flexion, abduction, and scaption) through 0° to 90°. Three movement speeds were used for each movement as determined by a metronome (30°/sec, 45°/sec, and 90°/sec). Dry-land maximal voluntary contraction tests were used to determine movement normalization. Results Muscle activity levels were significantly lower in water compared with dry land at 30°/sec and 45°/sec but significantly higher at 90°/sec. This sequential progressive activation with increased movement speed was proportionally higher on transition from gravity-based on-land activity to water-based isokinetic resistance. The pectoralis major and latissimus dorsi muscles showed higher activity during abduction and scaption. Conclusions These findings on muscle activation suggest protocols in which active flexion is introduced first at low speeds (30°/sec) in water, then at medium speeds (45°/sec) in water or on dry land, and finally at high speeds (90°/sec) on dry land before in water. Abduction requires higher stabilization, necessitating its introduction after flexion, with scaption introduced last. This model of progressive sequential movement ensures that early active motion and then stabilization are appropriately introduced. This should reduce rehabilitation time and improve therapeutic goals without compromising patient safety or introducing inappropriate muscle recruitment or movement speed.

Surface electromyography during physical exercise in water: A systematic review

Background Aquatic exercise has been widely used for rehabilitation and functional recovery due to its physical and physiological benefits. However, there is a high variability in reporting on the muscle activity from surface electromyographic (sEMG) signals. The aim of this study is to present an updated review of the literature on the state of the art of muscle activity recorded using sEMG during activities and exercise performed by humans in water. Methods A literature search was performed to identify studies of aquatic exercise movement. Results Twenty-one studies were selected for critical appraisal. Sample size, functional tasks analyzed, and muscles recorded were studied for each paper. The clinical contribution of the paper was evaluated. Conclusions Muscle activity tends to be lower in water-based compared to land-based activity; however more research is needed to understand why. Approaches from basic and applied sciences could support the understanding of relevant aspects for clinical practice.